In recent years, plate-type heat exchangers have been widely used in equipment such as air conditioners, refrigerators, water chillers and heat pumps. Generally, a plate-type heat exchanger comprises multiple heat exchange plates which are joined together by brazing, full welding, semi-welding etc. or in a dismantlable manner, with the spaces between the plates forming channels for the circulation of heat exchange fluid. When the heat exchange fluid flows through the channels, it contacts the heat exchange plates, and thereby achieves heat exchange.
FIG. 1(a) shows a type of heat exchange plate having an inverted-V-shaped pattern. As the figure shows, the heat exchange plate has a plate main body, with a concave-convex inverted-V-shaped pattern provided over the entire surface of the plate main body. Such a heat exchange plate can provide good distribution of fluid over the entire plate main body surface, and so can achieve high heat exchange efficiency. However, when such heat exchange plates are installed for example by brazing, full welding or semi-welding etc. or in a dismantlable manner, the inverted-V-shaped patterns of adjacent heat exchange plates are installed in opposite directions, i.e. a corresponding set of inverted-V-shaped patterns on two adjacent heat exchange plates only has two installation contact points when installed, and consequently, the strength of the entire plate-type heat exchanger is not high. Moreover, such heat exchange plates must not be too thin, otherwise the problem of strength not meeting requirements will likewise arise, resulting in a drop in the reliability of the entire plate-type heat exchanger.
FIG. 1(b) shows another type of common heat exchange plate having a “dimple” pattern. As the figure shows, the heat exchange plate has a plate main body, with multiple protrusions and recesses provided over the entire surface of the plate main body, wherein the multiple protrusions and recesses are spaced apart from one another. When a plurality of such heat exchange plates are installed, multiple protrusions on adjacent heat exchange plates are in contact with one another. Thus, compared with heat exchange plates having an inverted-V-shaped pattern, the transitional curved surface between protrusion and recess is more rational, and the distribution of installation contact points is also more rational, so that the entire plate-type heat exchanger has better strength. Moreover, the thickness of the heat exchange plate may be correspondingly reduced, so as to achieve the object of saving costs. However, the fluid distribution of this heat exchange plate is poorer than that of the heat exchange plate having an inverted-V-shaped pattern described above, so the heat exchange efficiency is affected.
Thus, there exists a need with regard to plate-type heat exchangers obtained by fitting together heat exchange plates; specifically, it is desired that the heat exchanger joining strength can be guaranteed and the cost of manufacturing the heat exchange plates can be reduced while ensuring good heat exchange efficiency, so as to reduce the cost of manufacturing plate-type heat exchangers.